3D Scanning in Grass Valley, CA

Grass Valley was built on hard-rock gold. The Empire Mine operated from 1850 to 1956 and left 367 miles of underground passages, reaching an incline depth of 11,007 feet in its final year. In 1932 it was connected underground to the neighboring North Star mine. The surface is now Empire Mine State Historic Park, 853 acres on the National Register since 1977, and its buildings include the Bourn Cottage, designed by Willis Polk in 1897 and built from the mine's own waste rock. Across town, the North Star Mine Powerhouse of 1895 drove the mine's compressed-air system with Pelton water wheels, including a 30-foot wheel that was the largest in the world at the time; it is now a museum. Stone buildings, heavy timber, and large machinery like this are slow to measure by hand and ideal for a scan, which records the whole structure without touching it. Work on public and museum property is done for, and on the terms of, whoever owns it.

Downtown, the Holbrooke Hotel is California Historical Landmark 914, one of many 19th-century commercial buildings on the city's hilly streets where floors step, walls lean, and old drawings are rare. Grass Valley is also a place where technology buildings change hands. The Grass Valley Group, the broadcast video equipment maker, was founded in the city in 1959; its former U.S. headquarters on Crown Point Court was sold in 2023. Reusing an office or light-industrial building like that starts with measured floor plans, column grids, ceiling heights, and slab deviation and levelness maps. Sierra Nevada Memorial Hospital and the Sierra College Nevada County campus, opened in 1996, round out the institutional buildings that need existing-conditions plans before renovation.

Grass Valley is a longer trip from our Lotus office than the Placer County cities, so we plan it as full field days. Control is GNSS primary and Trimble S3 secondary, held to 0.01 US survey feet relative to project control; scans are Trimble X9, processed in Trimble Business Center. You receive a registered, cleaned point cloud (E57, LAS, or RCP), scan-to-CAD plans, sections, elevations, 3D linework, and coded points, with a report stating the control basis and accuracy achieved. See 3D laser scanning, as-built surveys, scanning in Auburn, scanning across the Gold Country, and our Grass Valley surveying page.